pushing server side data to client and displaying via raphaeljs

rtext2.erl

%% -*- mode: nitrogen -*-
-module (rtext2).
-compile(export_all).
-include_lib("nitrogen_core/include/wf.hrl").
-include_lib("nitrogen_core/include/google_chart.hrl").
-include("records.hrl").

%% http://raphaeljs.com/text-rotation.html

main() -> #template { file="./site/templates/raphael.html" }.

title() -> "Todd's <b>Raphael Text Log</b> Page".

body() -> 

  Panel = #panel { style="margin: 50px 100px;", body=[
      #span { text="Raphael Log Test Below" },
      #panel { id=holder},
      #span { id=transfer, text="---------------" }
    ]},
  wf:comet(fun() -> bg_update(transfer, 1, 1000) end),
  wf:wire(#script { script="
      var hldr = obj('holder');
      var tx = obj('transfer');
      var setRText=function(text){
        console.log('setting text');
        var R = Raphael(hldr, 640, 480);
        var attr = {font: '50px Helvetica, Arial', opacity: 0.5};
        var txt = [];
        txt[0] = R.text(320, 240, text).attr(attr).attr({fill: 'hsb(0, .5, 1)'});
      };
      var scrapeElement=function(){
        setRText(tx.innerHTML);
        setTimeout('scrapeElement()', 1000)};
      scrapeElement();
      "}),
  wf:wire(transfer, #event { type=onAfterUpdate, actions=#script { script="
        setRText(obj('transfer').text);
        "}}),
  Panel.

event(E) ->
  wf:info("event: ~p~n", [ E ]).

bg_update(ControlID, Count, Delay) when Count > 5 ->
  % not invoking self again...but we are getting invoked?
  wf:info("count=~p~n", [ Count ]),
  ok;
bg_update(ControlID, Count, Delay)  ->
  timer:sleep(Delay),
  wf:update(ControlID, wf:to_list(Count)),
  wf:flush(),
  wf:info("count=~p~n", [ Count ]),
  bg_update(ControlID, Count + 1, Delay).